Roadway or pavement and method of constructing same



A. Rusa. ROADWAY 0R PAVFMENT AND METHOD 0F CONSTHUCTING SAME. APPLICATIN FILED QPR. 26, 19|?.

l,330,1439. lPmmi Feb.10,1920.

prepared .sugraa UNITED STATES PATENT OFFICE.

BERNARD A. RUGE, OF TARRYTOWN, NEW YORK, ASSIGNOR TO WARD CARPENTER AND COMPANY, INC., A CORPORATION 0F NEW YORK.

ROADWAY OR PAVEMENT AND METHOD OF CON STRUGTIN G SAME.

Application filed April 26, 1817.

To all [fr/om if may concern.'

Be it known that I. BERNARD A. RUGE, a citizen of the Vnited States, residing at 'Tarrytown county of IVestchester, and State of New York.Y have invented certain new and useful Improvements in Roadways or Pavements and Methods of Constructing Same, fully described and represented in the following specification and the accompanying drawings, formingr a part of the same.

This invention relates to certain improvements in roadways or pavements particularly adapted for automobiles and other heavy vehicle tralic. and method of constructing the same.

It is the especial object of the invention to provide a road construction which shall be very much cheaper. because of the material used. than prior constructions. and which, because ol' the materials and the method of laying them, will by` durable and will stand up for long periods under the heavy tratlic to which roadways are now subjected, particularly by the automobile. the construction being such that, except under unusual conditions, as swampy ground. no special foundation is required. the Inatcrials ot' the road being laid directly on the usual snbgrade of dirt or soil.

In modern road constructions. it has been the opinion of road engineers that die road ballast which is used with a binden should have the highest crushing strength. that is. offer the highest resistance to impact shocks. So, when obtainable, trap rock has been used which has such properties, many stones of less crushing strength being rejected as unfit. Trap rock. and for that matter most stone at all suitable for road making. is expensive, but has been considered essential.

I have discovered that coal cinder and similar material. which it is exceedingly de sirable to use because of its abundance and cheapncss. may. contrary to the usual belief of road engineers. be employed for road ballast in a substantially pin-e state. that to say. without. mixing it with other ballast material such as trap rock or softer stone or pebbles.

In road constructions where such ciuder has been used. the percentage of the cinder has been very small. it haviulgT been used. not as the ballast. but mixed with trap rock. broken stone or pebbles. and simply used as a filler between the rock interstices.

Specification of Letters Patent.

Patented Feb. 10, Serial No. 164,?90.

I have found by experiment that the use of a sul'istantially pure cinder combined in various ways with a bituminous binder will produce a road bed which will stand up for long periods and which is very much cheaper to construct than road beds employing trap rock or other broken stone or pebbles. This durability of a road constructed of a substantially pure cinder united with a binder and compacted. I attribute possibly to the elasticity of the material which. apparently, yields somewhat. or otl'ers an elastic, resistance. to the impact of shocks of vehicles passing over the roadway. this elastic lesistance preventing breaking. which is very apt to occur with roadways which are very hard, such as those in which crushed or broken stone. as trap rock or pebbles and some hardening agent. is employed. Furthermore, in addition to its eheapness, substantially pure coal cinder has the added advantage that it may be obtained from in"- uumerablc sources and is available by most municipalities as a waste product from their publie buildings. which may be utilized in road construction without any other ma.- terial except a bituminous binder.

My improved roadway or pavement is, tllereforcessentially one made of substantially pure coal cinder. and preferably suf-h ficiently clinkered and free from line ash so as not to disintegrate or Igrind up under the act-ion of the roller by which the bed is compacted. and combined with a bituminous binder as hereinafter described. As .an i11- stance of such cinder. I would specify the cinder ordinarily used for railroad ballast.

The accompan vingl drawing' illustrates two ways of carrying out my invention. In this drawing. Figure 1 is a cross sectional view showingthe invention as embodied iu a roadway havingr two layers of coal cinder and binder. and Fie: i a similar view .showinte` the roadway as constructed with one layer.

Various methods may be employed for building;v the roadway of this cindcr with a bituminous binder. depending' somewhat on the character of road to be built and the probable amount of tratlic which would be carried thercover. A construction which has givcn satistzwtory results. and which will prcl'crably be used where the traffic is heavy. may be constructed as follows: The dirt or soil of the road to be constructed is i layer,

removed to the desired subgrade. On the dirt or soil is first laid a layer of cinder which is of a minimum thickness of two inches. The thickness of this first cinder layer may vary accordinghto the character :of the road desired, but I ave found by experiment that six in ihes is usually sufficient. This cinder base is then rolled or compacted into a compact layer by means of any suitable roller of `sul'licient weight to effect the compacting but not suliieient to grind up the cinder, a roller of from five to ten tons usually b'eing employed. This cinder layer having been rolled, a coating of a4 bituminous. binder, such as heavy oil residuuni of petroleum distillation is applied in an suitable manner, as by s raying from a tan under pressure or spi-ea ing by hand. This binder may be applied either in a cold state,

or heated, the latter method, under certain circumstances, givin very good results, the binder being heate up to 75 to 100 F. This binder coating is allowed to percolate through the cinder, and with it forms a compact bed which at the same time may yield somewhat or have an elastic resistance to impact shocks. The binder may be used in any suitable quantities, de endin on the density of the particular ein er use and on the thickness of the layer, the quantity varying from three fourths of a gallon to a gallon and a half er square yard. After the binder has su ciently `permeated the cinder, a second layer of substantially pure cinder of a thickness of from two to four inches is applied and rolled as was the first and after the rolling there is applied a somewhat smaller amount of bituminous binder, the amount of the binder used in the second layer varying from one-quarter to three-quarters of a gallon per square yard, depending on the quality of cinder einloyed. For usual traliic conditions, a roaded constructed as described will'be of sulicient strength and durability and can be surfaced, asis usual, by spreading a thin coating of cinder or sand over the surface. After the second coating of binder has beeh applied, this cinder yor sand is preferably rolled in. If, however, tralc is expected to be ver heav over the road, a third layer of ein er an binder similar to the second layer may be put on and then the finishing coating of cinder or sand ap lied. 1f, in constructing the road as descr-i ed, after the cinder is rolled and before the application of the binder, the cinder should Apreset large interstices, a thin layer of cla or sand may be spread over the layers to lil up these iiiterstices before the binder is applied. This addition of cl'ay or sand is, however, unnecessary, and may be omitted, as generally the cinder particles will so vary in size as to compact without having these undesirably large interstices.

If it is desired, and this is true particularly where light traffic is expected over the roads, such, for instance, as roads built away from main lines of travel, the road may be constructed with a somewhat thicker base of the cinder ballast and but one coating of the binder. Where the road is to be so constructed, it has been found that a layer of six to ten inches or more of cinder placed on the dirt subgi-ade and rolled as before described will give very good results. After this has been rolled there Will be placed thereon a thinner layerof, say, two or three inches of cinder, which is then rolled and the binder ap lied as described, either hot or cold, and i desired then surfaced with a. thin layer of cinder or sand. If desired, however, for light traffic roads, this second thinner layer of cinder may be omitted and the binder applied directly to the rolled cinder base. If desired, a curb of any suitable character may be provided on each side of the road to prevent the pavement from raveling, this curb being so laid that it is flush with the surface of the completed road and being left in osition.

A roadway constructed as aliove described is one which may be built very cheaply be# cause of the absence of the expensive trap rock or other stone heretofore considered necessary, and because its material is at the disposal of practically every town, or which can be obtained at a minimum of expense, and a roadway be produced which is durable for long periods. Furthermore, such a roadway, should any settling take place, or should the road be injured, may be very easily re aired by simply removing the had spot, ad ing more cinder, a little binder, and rolling, Such a road is, therefore, very inexpensive to keep in repair. While the thicknesses of the cinder layers and the proportions per square yard of binder have een found in practice to be effective, it will be understood that different thicknesses of cinder layers may be employed and different proportions of binder used, depending on the particular character of road desired in any particular instance, and that the invention is niet restricted to the thicknesses and proportions set forth.

What is claimed is:

l. A vehicle roadway or pavement havin a foundation or ballasting rolled layer o substantially pure coal cinder said cinder being of a size suicient to withstand substantial disintegration or grinding up when rolled, a bituminous binder pereolated through such rolled layer, and a superimposed rolled layer of cinder and a bituminous binder therefor, said layers being of suilicient thickness to resist the impact of the expected load.

2. A vehicle roadway or pavement com-I 'prising a rolled layer of substantially pure 130 coal oinder of sucient thiclmss lo resist the impact, of the exper-tml lozul. `*uid vin der being of u size sulivioni to \\'itl1: l1uul substantial disintegration, or grindingnup when rolled, and a bituminous linilor upplicd to and percolnteil through tho rolled layer.

The mothorbof construrtingu wliiulc roadway or pzlvemvnt wllivh coubts in pra,

)airing n dirt subgmdo, puttingr flown a iuyvr of substantially puriI coul rinrli-r. rollY ing illu cinilor to comp:V it. uppgingf n `'gixtmninouf; binder fo/thiI rollwl Iaiyvr so tlml it"`ri1prgglgoffll@rutlirough, su l oiilnposing :i seifond layer of silbstnntiulLv puri con] "inrlvr, rolling tlm svrond layer to compmrt il. :unl applying' u bituminous liilnlcr to Hu: second layer, llu` Huid lnyvrs boing Sullivioutlj,Y tlm-k fo nilllstzinll t lu impart of tlm vxprrtmlJlond.

4. 'llu luollioil of constructing u voliiclv roadway ofvgmvonn'nt, wllirh wonsists in pro paring u dirt snligi'zulm puttin#V (lown :L lnhxfor of sulisfuulnlly puro coul vinder. of nfli-ilni thlcknvss to withstnncl tlw impuct of ilu: oxpvrliil loaul, rollingA tlm vinili-r to voiupzu'f it. :unl adding :i liituxninrum` binder to tlurollvfl Cindvr und allowingille binder in porrolulv through the layer.

1u ii-tlniony whorcof, I lun'u llorountoet *uy lmlnl.

BERNAR l) A. RUGF. 

